#coding:utf-8

from collections import Counter
'''
	a = {1,2,3,5,6}
	b = {1,7}
	c = {1,2,9}
	d = {5,6,8}
    输出出现n次的元素
'''
a = {1,2,3,5,6}
b = {1,7}
c = {1,2,9}
d = {5,6,8}

lst = [a,b,c,d]
cnt = Counter()

for i in lst:
	for j in i:
		cnt[j] +=1

print cnt.most_common(3)
print "----End---"

